Referring to FIG. 7, a prior art co-axial connector for a high-frequency cable 101 is provided with a center pin 104 which is connected electrically to a central conductor 103 of a co-axial cable 102. The center pin 104 is supported in the center of a molding insulator 105. An external terminal 106 is engaged with the periphery of the molding insulator 105. The external terminal 106 is connected electrically to an external conductor 107 of the co-axial cable 102 by a connecting piece 108, and supported mechanically on a plastic sheath 109 of the co-axial cable 102 by an anchoring piece 110. The external terminal 106 is provided with a longitudinal slit 111 until about the middle of the terminal in order to gain spring tension. A mold-insulating bushing 112 is provided on the periphery of the external terminal 106.
The prior art co-axial connector for high-frequency cable has the problem of requiring an accurate outer diameter for the molding insulator 105 because the molding insulator 105 engages the cylinder of the external terminal 106. The engagement of the molding insulator 105 and the external terminal 106 has created other problems in addition to the assembly problems already existing.
Furthermore, when the molding insulator 105 engages an engaging projection provided on the molding insulator 105, the engaging projection is attached to the end of an external terminal 106 during assembly. The attachment of the engaging projection to the external terminal 106 results in damage of the engaging projection and deformation of the external terminal 106.
Another structure was proposed to prevent the damage to projection and the deformation of the external terminal 106. This alternate structure included a slit provided axially to the cylinder of the external terminal 106 in order to adjust the inner diameter of the cylinder. However, the co-axial connector for a high-frequency cable with the alternate structure resulted in leakage of high frequency signals through the slit. Furthermore, the slit widened while in connection with another connector, causing a release of its engagement with the molding insulator so that the molding insulator slipped off the cylinder.
An object of the present invention is to provide a co-axial connector for a high-frequency cable which is convenient to assemble, which prevents high-frequency signals from leaking and which protects the molding insulator 105 from slipping off the external terminal 106.
Another object of the present invention is to provide a co-axial connector for a high frequency cable which protects an insulating bushing from slipping off earth metal fittings.